Question

A block is at rest on an inclined plane making an angle $\alpha$ with the horizontal. As the angle $\alpha$ of the incline is increased, the block starts slipping when the angle of inclination becomes $\theta$ . The coefficient of static friction between the block and the surface of the inclined plane is or A body starts sliding down at an angle $\theta$ to horizontal. Then coefficient of friction is equal to

• A. $\sin \theta$
• B. $\cos \theta$
• C. $\tan \theta$
• D. Independent of $\theta$

Answer 1

Answer: (C)

$\tan \theta$

Answer 2

Coefficient of friction = Tangent of angle of repose

$\therefore$ $\mu = \tan \theta$